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Rigid polyurethane foams from a polyglycerol-based polyol
PublicationRigid polyurethane foams (rPUs) were synthesized by replacing 35 and 70 wt.% of petrochemical polyol with polyglycerol. Two types of polyglycerol with different molecular weights and hydroxyl numbers were used to obtain new ‘‘green’’ polyurethane–polyglycerol foams. The foams were prepared by a single step method for the ratio of NCO/OH groups equal to 2. rPUs synthesized with polyglycerol showed regular cellular structure, with...
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Investigating the combined impact of plasticizer and shear force on the efficiency of low temperature reclaiming of ground tire rubber (GTR)
PublicationIn the present work, ground tire rubber (GTR) was mechano-chemically reclaimed at ambient temperature using two-roll mills. Road bitumen and styrene-butadiene-styrene (SBS)-modified bitumen at variable content (in range: 2.5–20 phr) were applied as reactive plasticizers to enhance reclaiming of GTR. For better understanding the plasticizing effect of bitumen on the quality of obtained reclaimed rubber, mechano-chemically reclaimed...
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Effect of high loading of titanium dioxide particles on the morphology and selected properties of natural rubber-based composites
PublicationThe aim of this work was to prepare and characterize the natural rubber vulcanizates contained different amounts of titanium dioxide particles. At first rubber mixture was prepared using a laboratory two-roll mill and then samples were vulcanized in a hydraulic press. The formulation of rubber mixture and rubber-processing technique is based on our earlier investigations. Materials were obtained at the different titanium dioxide...
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Rheological characteristics of oligomeric semiproducts gained via chemical degradation of polyurethane foam using crude glycerin in the presence of different catalysts
PublicationPolyurethane (PU) recycling is a topic of growing interest due to the increasing amount of polyurethane waste. The main purpose of polyurethane chemical recycling is to recover the starting polyol. In this study, a method of polyurethane thermochemical recycling, glycerolysis by means of crude glycerin, is proposed. This work presents a comparative study of commercial catalysts used in order to accelerate the decomposition process,...
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Synthesis and characterisation of polyurethane elastomers with semi-products obtained from polyurethane recycling
PublicationIn this work polyurethane elastomers were synthesised by using different mixtures of a petrochemical and glycerolysate polyols and 4,4-diphenylmethane diisocyanate (MDI). Glycerolysate polyol was produced from polyurethane foam decomposition using crude glycerine as a decomposition agent. The structure and thermal properties of obtained semi-product were similar to the polyol used in the synthesis of original foam. Glycerolysate...
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Oxygen concentration regulated the efficient liquefaction of vulcanized natural rubber
PublicationOxidative liquefaction represents a promising avenue for the homogeneous and high-value utilization of waste tire rubber. Given that truck tires predominantly comprise natural rubber (NR), this study investigated the efficient liquefaction of vulcanized NR regulated by oxygen concentration. Remarkably, the liquefaction of vulcanized NR was realized with an oxygen concentration of 75 % at 200 °C within 3 min. FTIR spectroscopy showed...
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Degradation of polyurethanes in sea water
PublicationOceniono degradowalność różnych poliuretanów w wodzie morskiej Bałtyku. Porównano te dane z wynikami stopnia degradacji poliuretanów w wodzie morskiej z dodatkiem azydku sosowego. Ocenę stopnia degradacji przeprowadzano na podstawie pomiarów zmian masy, właściwości mechanicznych i morfologii przed i po procesie degradacji. Wykazano, że różna podatność na degradację poliuretanów w wodzie morskiej związana jest z ich odmiennym stopniem...
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New Polymeric Materials for Solid Phase Extraction
PublicationSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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Polymers for burn dressings and skin substitutes
PublicationSkin burns belong to the group of the most complex injuries due to convoluted skin structure which includes nerve cells, muscles, sweat and sebaceous glands and blood vessels. Both on the market and at the research stage, there are many different dressing and skin substitutes proposals that utilize various materials and active substances. This chapter focuses on summarizing and describing the most popular polymer-based commercial...
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Conducting polymers for biodegradable metallic implants
PublicationNowadays permanent metallic cardiovascular stents are long-term implants. The long-time presence of such an implant in human body can cause overgrowth of tissue within the treated portion of the vessel, blockage of the circulatory system and many other clinical complications, such as thrombosis, prolonged physical irritations or chronic inflammation. Therefore, in recent years, there is an interest to create biodegradable metallic...
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Conducting polymers electrodeposited on active metals
PublicationPraca poświęcona studiom literaturowym doniesień dotyczących polimerów przewodzących, osadzanych na metalach aktywnych. Zastosowanie polimerów przewodzących jako warstw antykorozyjnych oraz elektrokrystalizacja metali na polimerach przewodzących zostały zebrane i przedstawione w tej pracy.
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Synthesis and electrochemical characteristics of novel dithiocarbamate polymers
PublicationNovel dithiocarbamate compounds have been obtained by reacting a linear poly(ethylenimine)polymer, MW 50,000, with CS2. The resulting anionic polymers contain, depending on the reaction conditions, up to two sulfur atoms per one nitrogen atom (approx. 40% w/w). The polymers are soluble in dimethylsulfoxide and insoluble in acetonitrile solutions. In both solvents they are electrochemically active, in the latter case as a cast film...
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Polyurethane nanocomposites obtained with organically modified montmorillonites.
PublicationW pracy przedstawiono wyniki badań dotyczące analizy właściwości i struktury nanokompozytu montmorylonit/poliuretan. Przeprowadzono pomiary właściwości mechanicznych i badania strukturalne z wykorzystaniem dyfrakcji promieni rentgenowskich i transmisyjnej mikroskopii elektronowej.
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Computational modelling of the modification of epoxy resins
PublicationSymulacja komputerowa właściwości fizycznych sieci żywic epoksydowych (DGEBA/DDM) modyfikowanych związkami akrylowymi przy użyciu programu Cheops® MillionZillion Software.
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Ionophores in polymeric membranes for selective ion recognition:impedance studies
PublicationW pracy badano dwa typy elektrod: membranowe elektrody jonoselektywne (ISE) oraz elektrody nowego typu all-solid-state (AAS). Elektrody AAS zawierają przewodzącą warstwę polimerową na węglu szklistym lub platynie, na który nałożona jest membrana zawierająca jonofor. Do badań użyto dwa jonofory: p-tert-butylokaliks[4]aren-korona-4 (L1) selektywnie kompleksująca jony Na+ oraz kaliks[4]aren-korona-6 (L2) selektywnie kompleksująca...
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The Escherichia coli RNA polymerase alpha subunit and transcriptional activation by bacteriophage lambda CII protein.
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A simple modification to improve the accuracy of methylation-sensitive restriction enzyme quantitative polymerase chain reaction
PublicationDNA digestion with endonucleases sensitive to CpG methylation such as HpaII followed by polymerase chain reaction (PCR) quantitation is commonly used in molecular studies as a simple and inexpensive solution for assessment of region-specific DNA methylation. We observed that the results of such analyses were highly overestimated if mock-digested samples were applied as the reference.We determined DNA methylation levels in several...
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Characterization of Aliphatic Polyesters Synthesized via Enzymatic Ring-Opening Polymerization in Ionic Liquids
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Poly(ferrocenylsilane-block-methacrylates) via sequential anionic and atom transfer radical polymerization.
PublicationArtykuł przedstawia sposób otrzymywania kopolimerów blokowych poli(ferrocenylosilanów) (PFS) i poli(metakrylanu metylu) (PMMA). W pierwszej kolejności syntezowany jest anionowo blok PFS, który po odpowiedniej terminacji służy jako makroinicjator dla syntezy bloku PMMA. Synteza ta jest realizowana przy użyciu polimeryzacji rodnikowej z przeniesieniem atomu (ATRP), katalizowanej przez kompleksy rutenu. Otrzymane w ten sposób kopolimery...
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Tuning of the Electrochemical Properties of Transparent Fluorine-doped Tin Oxide Electrodes by Microwave Pulsed-plasma Polymerized Allylamine
PublicationWe report here the dry, one-step, and low-temperature modification of FTO surfaces using pulsed plasma polymerization of allylamine (PPAAm). PPAAm/FTO surfaces were characterized by X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and contact angles to understand the morphological, structural, and optical properties. FTO were coated with a very thin layer of adherent cross-linked, pinhole-, and additive-free allylamine...
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The use of CAD applications in the design of shredders for polymers
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Electroconducting polymers as a corrosion protection materials review
PublicationAutorzy przywołują 89 pozycji literaturowych dotyczących użycia polimerów elektroaktywnych w ochronie metali przed korozją. Wykazano, że najczęściej wykorzystywany w tym celu jest polipirol. Przytoczone prace dotyczą ochrony stali, aluminium, cynku oraz stopów magnezu.
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Swelling effects in cross-linked polymers by thermogravimetry
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Hydrogels Based on Natural Polymers for Cardiac Applications
PublicationIn this work agar- and borax-based hydrogels with and without the addition of poly(vinyl alcohol) (PVA) at different concentrations were synthesized. Hydrogels were modified by the same amount of acetylsalicylic acid (ASA) which exhibits antithrombotic properties. The effect of modification by ASA on the properties of hydrogels was analyzed.
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Molecularly imprinted polymers for the detection of volatile biomarkers
PublicationIn the field of cancer detection, the development of affordable, quick, and user-friendly sensors capable of detecting various cancer biomarkers, including those for lung cancer (LC), holds utmost significance. Sensors are expected to play a crucial role in the early-stage diagnosis of various diseases. Among the range of options, sensors emerge as particularly appealing for the diagnosis of various diseases, owing to their cost-effectiveness,...
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Taq DNA polymerase fused with DNA binding protein with increased resistance to inhibitors from clinical samples
PublicationNowadays PCR method is commonly used in molecular diagnostic. However, in many cases PCR is limited, by the presence of inhibitory substances in biological, soil or food samples Efficiency and fidelity of amplification is strongly connected with DNA polymerase and reaction conditions. To meet the requirements of modern diagnostic methods it is essential to seeking for new DNA polymerases with better properties useful in these field....
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Increased concentration of Taq DNA polymerase as a solution for GC-rich templates from clinical and environmental samples
PublicationDNA polymerase is an enzyme which plays crucial role in replication and DNA repair. It found application in PCR (polymerase chain reaction) where catalyses process of in vitro DNA synthesis. To meet the demands posed by mod- ern diagnostic, molecular biology or genetic engineering it is necessary to improve DNA polymerases to obtain new or better features useful in these fields. So far implemented modifications in majority are...
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An analytic approach to the conductance and I-V characteristics of polymeric chains
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Behaviour of asymmetric structures with base isolation made of Polymeric Bearings
PublicationEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Seismic excitations cause a lot of damage in a wide variety of ways, leaving thousands of casualties in their wake. During the last few years alone, the world has witnessed many major earthquakes, five of which have caused far-reaching consequences of a national scale for Haiti (January 2010), Chile (February...
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Behaviour of Asymmetric Structure with Base Isolation Made of Polymeric Bearings
PublicationEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Seismic excitations cause a lot of damage in a wide variety of ways, leaving thousands of casualties in their wake. Due to randomness of earthquake occurrence, lack of visible causes and their power of destructiveness, structural engineers need to develop new technical solutions and protection systems against...
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Electronic excitation energy migration in partly ordered polymeric films
PublicationWieloetapowa migracja energii pomiędzy podłużnymi fluoroforami (karbocyjaniny) w osiowo rozciąganych foliach polimerowych była studiowana na podstawie pomiarów anizotropii emisji i symulacji Monte Carlo. W przeciwieństwie do układów nieuporządkowanych pokazano eksperymentalnie, że stężeniowa depolaryzacja fluorescencji w osiowo orientowanych foliach jest ekstremalnie słaba, mimo tego, że zachodzi zjawisko migracji energii. Opierając...
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On the Equations of the Surface Elasticity Model Based on the Theory of Polymeric Brushes
PublicationMotivating by theory of polymers, in particular, by the models of polymeric brushes we present here the homogenized (continual) two-dimensional (2D) model of surface elasticity. A polymeric brush consists of an system of almost aligned rigid polymeric chains. The interaction between chain links are described through Stockmayer potential, which take into account also dipole-dipole interactions. The presented 2D model can be treated...
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Modeling and Evaluation of Electric Treeing Phenomena in Polymeric Cable Insulation
PublicationThis paper investigates the treeing phenomenon in polymeric materials such as crosslinked polyethylene (XLPE) that is widely used in medium and high voltage power cables as primary insulation. The modeling of electrical tree growth in the insulation from its initiation to breakdown is significant research work that illustrates the discharge dynamics and its impact on aging process in polymeric insulation. This study utilizes pulse...
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Ionophores in polymeric membranes for selective ion recognition; impedance studies
PublicationBadania impedancyjne membran zawierających jonofory selektywne na kation Na+ (L1) i Cs+(L2) wykazały, ze stala dielektryczna materiału membrany zależy od typu uzytego plastyfikatora i zmienia się w zakresie od 28 do 60. Rezystancja membran zawierających ligand L1 i L2 wynosi 0.15 -1.4 Mohm w zależności od stężenia elektrolitu zewnnetrznego. Testowona dwa typy elektrod jonoselektywnych: elektrody typu ASS z polimerem przewodzącym...
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Gas sensors based on conducting polymers-recent developments
PublicationThis work discusses sensing performance dependence of PEDOT polymer and its composites on the counter ions used in the polymerization process. The sensors based on PEDOT-RGO composite show reversible response to NO2, while on PEDOT/LiClO4 irreversible. As a result, PEDOT-RGO could be used as a typical gas sensor, while sensor based PEDOT/LiClO4 could be used as an integrating gas sensor, also known as an accumulating gas sensor....
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NMR relaxation enhancement in gels polymerized and cross-linked by ionizing radiation: A new approach to 3D dosimetry by MRI
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Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublicationA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
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Compatibilization of polymeric composition filled with ground tire rubber – short review
PublicationWaste rubber is recognized as valuable materials resource and searching for new recycling methods is the main activity of many research institutions and companies. At the turn of the last years only few scientific papers about foamed polymer compositions filled with ground tire rubber were published. In paper review about progress in compatibilization and foaming of polymeric compositions filled with ground tire rubber.
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Degradation of polyurethanes in Compost Under Natural Conditions
PublicationThe estimation of degradibility of different polyurethanes under natural weather depending conditions in compost pile was the subject of the studies. The incubation of polymer samples took place for a period up to 24 months. The characteristic parameters of the compost: temperature, pH, moisture content, and activity of dehydrogenasis were monitored and their influence on degradation of polyuiretahnes was discussed. The compostability...
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Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites
PublicationThis study describes the development of a new class of high-performance polyurethane elastomer nanocomposites containing reduced graphene oxide (RGO) or graphene nanoplatelets (GNP). Two types of polyurethane elastomers with different contents of hard segments (HS) were used as a polymer matrix. The developed nanocomposites were characterized by thermal analysis (DSC, TG), dynamic mechanical testing (DMA), hardness testing, mechanical...
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Starch‐graft copolymers of N‐vinylformamide and acrylamide modified with montmorillonite manufactured by reactive extrusion
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Design and fabrication of flexible poly(vinyl chloride) dielectric composite reinforced with ZnO microvaristors
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Effect of ionic liquids on the structural, thermal, andin vitrodegradation properties of poly(ε-caprolactone) synthesized in the presence ofCandida antarcticalipase B
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Porous carbon nanosheet with high surface area derived from waste poly(ethylene terephthalate) for supercapacitor applications
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Poly(vinyl alcohol)/GO-MMT nanocomposites: Preparation, structure and properties
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Sustainable polylysine conversion to nitrogen‐containing porous carbon flakes: Potential application in supercapacitors
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Mechanism of MxOynanoparticles/CNTs for catalytic carbonization of polyethylene and application to flame retardancy
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Model studies on then-alkane emulsions stability
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Time Dependent Influence of Rotating Magnetic Field on Bacterial Cellulose
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Solid-phase microextraction and ion chromatographic analysis of anions based on polypyrrole electrode
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